diff --git a/conntrackt/models.py b/conntrackt/models.py
--- a/conntrackt/models.py
+++ b/conntrackt/models.py
@@ -1,8 +1,8 @@
-# Django-specific imports
+# Django imports.
 from django.core.exceptions import ValidationError
 from django.db import models
 
-# Create your models here.
+
 class Project(models.Model):
     """
     Implements a model with information about a project. A project has some
@@ -15,8 +15,8 @@ class Project(models.Model):
       description - Free-form description of the project.
     """
 
-    name = models.CharField(max_length = 100)
-    description = models.TextField(blank = True)
+    name = models.CharField(max_length=100)
+    description = models.TextField(blank=True)
 
     def __unicode__(self):
         """
@@ -26,6 +26,7 @@ class Project(models.Model):
 
         return self.name
 
+
 class Location(models.Model):
     """
     Implements a model with information about location. Locations can further be
@@ -50,8 +51,8 @@ class Location(models.Model):
       description - Free-form description of a location.
     """
 
-    name = models.CharField(max_length = 100)
-    description = models.TextField(blank = True)
+    name = models.CharField(max_length=100)
+    description = models.TextField(blank=True)
 
     def __unicode__(self):
         """
@@ -61,6 +62,7 @@ class Location(models.Model):
 
         return self.name
 
+
 class Entity(models.Model):
     """
     Models an entity in a project. An entity can be a server, router, or any
@@ -81,8 +83,8 @@ class Entity(models.Model):
       located.
     """
 
-    name = models.CharField(max_length = 100)
-    description = models.TextField(blank = True)
+    name = models.CharField(max_length=100)
+    description = models.TextField(blank=True)
     project = models.ForeignKey(Project)
     location = models.ForeignKey(Location)
 
@@ -106,6 +108,7 @@ class Entity(models.Model):
 
         return "%s (%s - %s)" % (self.name, self.project, self.location)
 
+
 class Interface(models.Model):
     """
     Models a representation of an interface on an entity. It can be used for
@@ -126,11 +129,11 @@ class Interface(models.Model):
       denoting the network netmask.
     """
 
-    name = models.CharField(max_length = 100, default = 'eth0')
-    description = models.TextField(blank = True, default = 'Main network interface.')
+    name = models.CharField(max_length=100, default='eth0')
+    description = models.TextField(blank=True, default='Main network interface.')
     entity = models.ForeignKey(Entity)
     address = models.IPAddressField()
-    netmask = models.IPAddressField(default = '255.255.255.255')
+    netmask = models.IPAddressField(default='255.255.255.255')
 
     def __unicode__(self):
         """
@@ -145,6 +148,7 @@ class Interface(models.Model):
         else:
             return '%s (%s/%s)' % (self.entity.name, self.address, self.netmask)
 
+
 class Communication(models.Model):
     """
     Models a representation of allowed network communication. This lets the user
@@ -183,11 +187,11 @@ class Communication(models.Model):
         ('ICMP', 'ICMP'),
         )
 
-    source = models.ForeignKey(Interface, related_name = 'source_set')
-    destination = models.ForeignKey(Interface, related_name = 'destination_set')
-    protocol = models.CharField(max_length = 10, choices = PROTOCOL_CHOICES)
-    port = models.IntegerField(default = 0)
-    description = models.TextField(blank = True)
+    source = models.ForeignKey(Interface, related_name='source_set')
+    destination = models.ForeignKey(Interface, related_name='destination_set')
+    protocol = models.CharField(max_length=10, choices=PROTOCOL_CHOICES)
+    port = models.IntegerField(default=0)
+    description = models.TextField(blank=True)
 
     def __unicode__(self):
         """